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Brett Wood
9,805 PointsMath::sqrt(9) vs Math.sqrt(9)
So this is kind of tripping me up a bit. Running puts Math::sqrt(9) and puts Math.sqrt(9) both return 3.0. It seems that sqrt is both a method inside the Math module and a method inside the Math class. Why are there two methods for sqrt?
1 Answer
William Li
Courses Plus Student 26,868 PointsIt seems that sqrt is both a method inside the Math module and a method inside the Math class.
Not quite, Ruby only comes with one sqrt() method, and it's defined at the Math module. Math::sqrt(9) and Math.sqrt(9) have no difference, Ruby allows you to use these 2 notations interchangeably when calling the instance method, though, by convention, dot notation is the preferred way.
However, you have to use the :: notation to access the constants, nested modules, or non instance methods defined within module/class.